The Facts About Income Tax Millions faithfully file their 1040 forms each April. But some things about federal income taxes may surprise you. Share | Related Content Making Your Tax Bracket Work Have you explored all your options when it comes to managing your taxable income? Does Your Child Need to File an Income Tax Return? When your child has income, there’s a good chance that he or she will need to report it and pay taxes. Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates.